RFC7217 introduces an alternative mechanism for creating addresses during
stateless IPv6 address configuration. It's supposed to create addresses whose
host part stays stable in a particular network but changes when the hosts
enters another network to mitigate possibility of tracking the host movement.
It can be used alongside RFC 4941 privacy extensions (temporary addresses)
and replaces the use of RFC 4862 interface identifiers.
The address creation mode is controlld by ip6.addr_gen_mode property
(ADDR_GEN_MODE in ifcfg-rh), with values of "stable-privacy" and "eui-64",
defaulting to "eui-64" if unspecified.
The host part of an address is computed by hashing a system-specific secret
salted with various stable values that identify the connection with a secure
hash algorithm:
RID = F(Prefix, Net_Iface, Network_ID, DAD_Counter, secret_key)
For NetworkManager we use these parameters:
* F()
SHA256 hash function.
* Prefix
This is a network part of the /64 address
* Net_Iface
We use the interface name (e.g. "eth0"). This ensures the address won't
change with the change of interface hardware.
* Network_ID
We use the connection UUID here. This ensures the salt is different for
wireless networks with a different SSID as suggested by RFC7217.
* DAD_Counter
A per-address counter that increases with each DAD failure.
* secret_key
We store the secret key in /var/lib/NetworkManager/secret_key. If it's
shorter than 128 bits then it's rejected. If the file is not present we
initialize it by fetching 256 pseudo-random bits from /dev/urandom on
first use.
Duplicate address detection uses IDGEN_RETRIES = 3 and does not utilize the
IDGEN_DELAY delay (despite it SHOULD). This is for ease of implementation
and may change in future. Neither parameter is currently configurable.
Having a static string buffer for convenience is useful not only
for platform. Define the string buffer in NetworkManagerUtils.h,
so that all to-string functions can reuse *one* buffer.
Of course, this has the potential danger, that different
to-string method might reuse the same buffer. Hence, low-level
library functions are adviced to use their own buffer, because
an upper level might already use the global buffer for another
string.
Support a new configuration option
[.config]
enable=<ENABLED>
for configuration snippets.
This new [.config] section is only relevant within the snippet itself
and it is not merged into the combined configuration.
Currently only the "enable" key is supported. If the "enable" key is
missing, it obviously defaults to being enabled. It allows snippets
to be skipped from loading. The main configuration "NetworkManager.conf"
cannot be skipped.
<ENABLED> can be a boolean value (false), to skip a configuration
snippet from loading.
It can also be a string to match against the NetworkManager version,
like "enable=nm-version-min:1.1,nm-version-min:1.0.6"
There are several motivations for this:
- the user can disable an entire configuration snippet by toggeling
one entry.
This generalizes the functionality of the global-dns.enable
setting, but in a way that applies to configuration on a per-file
basis.
- for developing, we often switch between different versions of
NetworkManager. Thus, we might want to use different configuration.
E.g. before global-dns options, I want to use "dns=none" and manage
resolv.conf myself. Now, I can use global-dns setting to do that.
That can be achieved with something like the following (not exactly,
it's an example only):
[.config]
enable=nm-version-min:1.1
[main]
dns=default
[global-dns-domain-*]
nameserver=127.0.0.1
Arguably, this would be more awesome, if we would bump our micro devel
version (1.1.0) more often while developing 1.2.0 (*hint*).
- in principle, packages could drop configuration snippets and enable
them based on the NetworkManager version.
- with the "env:" spec, you can enable/disable snippets by configuring
an environment variable. Again, useful for testing and developing.
This is effectively the same as nm_config_parse_boolean(). The difference is,
that "nm-config.c" is not available to the interface-helper, thus any
code used by interface-helper (like "NetworkManager.c") cannot use this
function.
Still don't drop nm_config_parse_boolean() entirely, because it's better
to have the explicit notion of parsing a string in the config-context.
I ended up not using the function. But I'd still keep this patch.
Port remaining bits to gdbus and remove stray dbus-glib references
Drop the dbus-glib version check from configure, since nothing depends
on new dbus-glib any more.
Move nm-dbus-glib-types.h and nm-gvaluearray-compat.h from include/ to
libnm-util/ since they are now only used by libnm-util and libnm-glib.
Previously, the order of destructing singleton instances
was undefined. Now, have singleton instances register their
destruction via nm_singleton_instance_register().
Objects that are registered later, will be destructed earlier. IOW,
they will be destroyed in reverse order of construction.
This is only a crude method to get the lifetime of singleton instances
right by default. Having singletons ref other singletons to keep them
alive gives more control over the lifetimes of singletons. This change
of having a defined order of destruction does not conflict with taking
references to singletons (and thus extending their lifetime).
Note that previously, NMPlatform was not registered for destruction.
We don't change that yet and intenionally leak a reference.
Move D-Bus export/unexport handling into NMExportedObject and remove
type-specific export/get_path methods (export paths are now specified
at the class level, and NMExportedObject handles the counters for all
exported types automatically).
Since all exportable objects now use the same get_path() method, we
can also add some helper methods to simplify get_property()
implementations for object-path and object-path-array properties.
Rather than randomly including one or more of <glib.h>,
<glib-object.h>, and <gio/gio.h> everywhere (and forgetting to include
"nm-glib-compat.h" most of the time), rename nm-glib-compat.h to
nm-glib.h, include <gio/gio.h> from there, and then change all .c
files in NM to include "nm-glib.h" rather than including the glib
headers directly.
(Public headers files still have to include the real glib headers,
since nm-glib.h isn't installed...)
Also, remove glib includes from header files that are already
including a base object header file (which must itself already include
the glib headers).
We have a special implemenation nm_match_spec_split() to split
a string. We also need the reverse operation to be able to convert
a list of specs to string without loss.
kill(pid,sig) can return success for zombie processes. This
caused nm_utils_kill_process_sync() to hang indefinitely.
Fix it by also checking the process state.
We don't want error logging for nm_platform_link_add() which
tries to load the bonding module. Later we will run tests as non-root,
where modprobe will fail. Logging an error would break the tests.
Code that is testable often needs special hooks to work
both for unit-tests and production.
Add a function nm_utils_get_testing() that returns whether
the code is run as part of a unit-test.
For non-testing mode, nm_utils_get_testing() will return
zero (NM_UTILS_TEST_NONE). For unit tests, the test should call
_nm_utils_set_testing() to configure tested functions.
By specifing the @flags attribute, the test can enable/disable
specific behaviors.
https://bugzilla.gnome.org/show_bug.cgi?id=701112
ASSERT_VALID_PATH_COMPONENT() always returns the input argument --
unless it fails an assertion and terminates the program. No need
to require the user to use the return value.
Some device types (s390 OSA and ipvlan) can use the same link-layer address
for multiple virtual interfaces, and the kernel used the dev_id property
to differentiate these devices when constructing the IID. NM should do
this too to prevent IID clashes.
https://bugzilla.redhat.com/show_bug.cgi?id=1101809
Of special note is the new D-Bus rule to allow root to talk to
org.freedesktop.NetworkManager.VPN.Plugin, without which NetworkManager
would not hear signals from the VPN plugins. Oddly, this worked
fine with dbus-glib...
https://bugzilla.gnome.org/show_bug.cgi?id=745307
There are currently three device spec properties: 'main.ignore-carrier',
'main.no-auto-default' and 'keyfile.unmanaged-devices'.
The first two, called g_key_file_parse_value_as_string() to split
the string into individual device specs. This uses ',' as separator
and supports escaping using '\\'.
'keyfile.unmanaged-devices' is split using ',' or ';' as separator
without supporting escaping.
Add a new function nm_match_spec_split(), to unify these two behaviors
and support both formats. That is, both previous formats are mostly
supported, but obviously there are some behavioral changes if the string
contains one of '\\', ',', or ';'.
nm_match_spec_split() is copied from glibs g_key_file_parse_value_as_string()
and adjusted.
Extend nm_match_spec_*() to support an "except:" prefix to negate
the result of a match. "except:" only works when followed by
an exact match type, for example "except:interface-name:vboxnet0",
but not "except:vboxnet0".
A matching "except:" spec always wins, regardless of other positive
matchings.
Add nm_utils_setpgid() as a g_spawn*() child setup function for
calling setpgid(), and use it where appropriate rather than
reimplementing it every time.
